What Do Bumps On Penis Indicate?

I masturbated for two consecutive times and havent had a long sleeping hours for two days and i noticed an area on the bottom part lower left middle side of my penile part and there are different sizes of bumps some are small and the other one is the biggest. Before I encountered this but just took a week i think this is some kind of iritation or friction due to masturbation or is it a herpes im not sure of Doc.